Spark plug



L. E. KOTTMEYER.

SPARK PLUG.

APPLICATION FILED JUNE 28,1920.

' INVENTORP WITNESS:

OFFICE.

LOUIS E. KOTTMEYER, OF RHINELAND, MISSOURI.

SPARK PLUG.

Specification of Letters Patent.

Patented May a, 1922.

Application filed June 28, 1920. Serial No. 392,288.

To all whom it may concern:

Be it known that I, Louis E. Ko r'rivrnvnn, a citizen of the United States, reslding at -Rhine1and, in the county of Montgomery,

State of Missouri, have invented a new and useful Improvement in Spark Plugs, of which the following is a specification.

This invention has for its prime object the provision of a simple, inexpensive and efficient spark plug for internal combustion engines comprising a stationary electrode depending from the porcelain core of the plug and a vertically movable electrode adapted to contact with the stationary electrode on the exhaust and suction strokes of the piston with suflicient force to dislodge the usual accumulation of carbon from. both electrodes and thus insure proper ignition.

In the accompanying drawing, Figure l is an elevation of a plug embodying my invention, with the lower portion thereof in section to disclose the relation and construction of the electrodes; Figure 2 a sec tional detail view of the base of the plug taken from an aspect opposite to that of Figure 1; and Figure 3 a cross-section taken along line 33 of Figure 1.

In common with spark lugs of ordinary construction now generally used, the plug of my invention comprises a porcelain core 1 disposed within a metal shell 2 secured by nut 3. Projecting vertically through said core is a stationary electrode terminating above in a binding-post 4: and below in a hook 5, said post carrying a nut 6 bearing against washers 7 and a thumb-nut 8 for securing the terminals of wires leading from the usual electrical distributor (not shown).

Depending from the lower edge 2 of shell 2 is a curved arm 9 provided with a chamber 10 disposed directly beneath hook 5 within which is a plunger 11 forming the movable electrode hereinabove mentioned, the base of said chamber being restricted as at 10 to afford a space beneath the plunger when the latter is seated. Said plunger is formed with a collar 12 substantially corresponding in diameter with the bore of said chamber and its lower extremity is enlarged to the circumference of said collar so as to maintain the plunger in true vertical position within said chamber during its reciprocal movement as hereinafter described, it being noted that the stem of the plunger intermediate said extremity and collar is comparatively slender.

The operation is as follows. Throughout the compresslon stroke of the usual fourcycle engine, plunger 11 remains seated within chamber 10 as shown in the drawing and upon completion of said stroke the spark which lgnites the charge jumps from one to the other electrode just as when a plug of standard type is used. Upon ignition a quantity of the burnt gas will be forced past collar 12 and the enlarged lower extremity of plunger 11 into chamber 10 and. its restricted portion 10", and when drawn out by the exhaust stroke of the piston this gas will serve to lift said plunger so that its upper extremity will strike hook 5 with suflicient force to dislodge the usual accumulation of carbon from both electrodes and thus insure an intense, hot spark upon completion of the compression stroke.

Moreover, during the suction or intake stroke of the piston said plunger will again be llfted into contact with said hook by passage of the fresh gas into said chamber and this second contact of the electrodes insures the removal of such carbon deposit as may have adhered after the contact first mentioned.

It will be appreciated that the hooked formation of the lower end of the stationary electrode is a distinct advantage in that it produces a larger spark than the ordinary straight electrode and may, be easily bent upward or downward with a pair of plyers so as to increase or diminish the space between the sparking points.

Having thus fully described the structure of the plug and its manner of operation, what I claim as new and desire to secure by Letters-Patent is 1. A spark plug'for internal combustion engines comprising a stationary electrode, a chamber disposed opposite and adj acent thereto, and a plunger fitting loosely within said chamber, the base of said chamber being restricted to provide a space beneath the plunger when the latter is seated, whereby the plunger may be intermittently movedinto contact with said electrode by aid of the gas within the engine.

2. A spark plug for internal combustion engines comprising a stationary electrode, a chamber disposed opposite and adjacent thereto, and a plunger fitting loosely within said chamber having a collar adjacent its upper extremity substantially corresponding in diameter With the bore of said chamber and a portion intermediate its lower extremity and said collar of smaller diameter than said bore, whereby the plunger may be intermittently moved into contact with said electrode by aid of the gas within the engine.

- LOUIS E. KOTTMEYER.

Witnesses ALVIN F. STRUTTMANN, B. J. GOsEN. 

